Sheet manufacturing method

ABSTRACT

A sheet manufacturing method includes a step of mixing fibers and a composite integrally including a resin and a coagulation inhibitor and a step of bonding the fibers and the composite. The composite is a powder whose volume average particle diameter is 1 μm or more to 100 μm or less, and at least a portion of the coagulation inhibitor is arranged in a surface of the composite.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 15/023,064, filed on Mar. 18, 2016. The entire disclosures ofU.S. patent application Ser. No. 15/023,064, International ApplicationNo. PCT/JP2014/004012, Japanese Patent Application No. 2013-206157,filed on Oct. 1, 2013, and Japanese Patent Application No. 2014-124057,filed on Jun. 17, 2014 are incorporated by reference herein.

TECHNICAL FIELD

The present invention relates to a sheet manufacturing apparatus, asheet manufacturing method, a sheet manufactured with the same, acomposite used therewith and an accommodation container therefor.

BACKGROUND ART

Depositing a fiber-like material and causing a bonding force between thedeposited fibers to obtain a sheet-like or film-like formed body hasbeen performed for a long time. Typical examples thereof includemanufacturing paper by pulp molding (paper-forming) using water. Even inpresent times, pulp molding is widely used as an example of a method ofmanufacturing paper. The paper manufactured by pulp molding generallyincludes a structure by cellulose fibers derived from wood or the likebeing entangled with one another, and being partially bonded to oneanother by a binder (paper strengthening agent (such as a starch pasteand a water-soluble resin)).

According to the pulp molding, it is possible for the fibers to bedeposited in a state where uniformity is favorable, and, in a case wherea paper strengthening agent is used in the bonding between fibers, it ispossible for the paper strengthening agent to be dispersed (distributed)in a state where the uniformity in the paper surface is good. However,because the pulp molding is a wet method, it is necessary to use largevolumes of water, and the necessity of dewatering and drying or the likearises after forming the paper, and therefore the energy or timeconsumed is extremely large. It is necessary to suitably process thewater used as waste water. Accordingly, it is difficult to respond tomodern demands for energy savings, environmental protection, and thelike. The apparatuses used in pulp molding frequently need large scaleutilities and infrastructure such as water, power, and drainagefacilities, and size reductions are difficult. From this viewpoint,there is an expectation of methods, referred to as dry methods, that useno or almost no water as paper manufacturing methods in place of pulpmolding.

PTL 1 discloses a waste paper board formed by mixing and defibratingwaste paper pulp and a thermal fusion bondable powder with a dry method,and subjecting these to hot pressing or the like.

CITATION LIST Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No. 09-019907

SUMMARY OF INVENTION Technical Problem

In the manufacturing of a sheet, there are cases of blending a coloringmaterial (such as a pigment) in order to adjust the tone of the sheet.PTL 1 does not disclose the using of a coloring material. In a case ofusing a coloring material, there are cases where the pigment is detacheddue to outside forces such as undulation, impact, abrasion or the likein a case of forming a sheet by simply mixing the coloring material.

There are cases where the thermal fusion bondable powders coagulate witheach other by simply mixing. In this case, when forming a sheet, aproblem arises of possibly forming parts where the thermal fusionbondable powder becomes rough, not sufficiently bonding the pulp to eachother at these parts, and lowering the strength of the sheet.

Solution to Problem

The invention was created in order to solve at least a part of the aboveproblems, and can be realized in the following aspects or applicationexamples.

According to an aspect of the invention, a sheet manufacturing methodcomprises a step of mixing fibers and a composite integrally including aresin and a coagulation inhibitor and a step of bonding the fibers andthe composite. The composite is a powder whose volume average particlediameter is 1 μm or more to 100 μm or less, and at least a portion ofthe coagulation inhibitor is arranged in a surface of the composite.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of the main portions of a sheet manufacturingapparatus according to an embodiment.

FIG. 2 is a schematic view of the sheet manufacturing apparatusaccording to the embodiment.

FIG. 3 is a diagram showing an example of a configuration of the sheetmanufacturing apparatus.

FIG. 4 shows schematic views of several examples of cross-sections of acomposite according to the embodiment.

DESCRIPTION OF EMBODIMENTS

Below, various embodiments of the invention will be described. Theembodiments described below are for describing examples of theinvention. The invention is not limited in any way by the followingembodiments, and includes various modifications carried out in a rangenot departing from the gist of the invention. Not all of theconfigurations explained below are indispensable configurations in theinvention.

1. SHEET MANUFACTURING APPARATUS

The sheet manufacturing apparatus 1000 according to the embodiment isprovided with a mixing unit 100 and a bonding unit 200. FIG. 1 is aschematic view of the main portions of the sheet manufacturing apparatus1000 according to the embodiment. FIG. 2 is a schematic view of thesheet manufacturing apparatus 1000 according to the embodiment. FIG. 3is a diagram showing an example of a configuration of the sheetmanufacturing apparatus 1000 of the embodiment. The sheet manufacturingapparatus 1000 is provided with at least a mixing unit 100 and a bondingunit 200.

1.1. Mixing Unit

The mixing unit 100 has the function of causing the fibers (fibrousmaterial) and the composite integrally including a resin and a coloringmaterial to be mixed. At least the fibers and the composite are mixed inthe mixing unit 100.

In the specification, there are cases where one fiber is indicated andcases where an aggregate of a plurality of fibers (a state such ascotton) is indicated when referring to fibers, a material in which aplurality of fibers is included is indicated when referring to a fibrousmaterial, and the meaning of a fiber bundle and the meaning of amaterial (powder or cotton-like substance) that is a raw material in asheet are included.

In the specification, particles formed with resin as a main componentintegrated with other components are referred to when referring to thecomposite. Although other components refers to coloring materials orcoagulation inhibitors, and the like, shapes, sizes, materials orcomponents having functions different to the resin that is the maincomponent are also included.

When referring to the coloring material in the specification, caseswhere the substance itself is able to color the sheet and cases where anaggregation (powder) of particles formed from a substance able to colorthe sheet are included. The meaning of a sheet raw material is furtherincluded when referring to a coloring material.

In the specification, the wording “the fibers and the composite aremixed together” is defined as the composite being positioned between thefibers in a space (system) with a fixed volume.

As long as the mixing unit 100 is able to mix the fibers (fibrousmaterial) and the composite together, the composition, the structure,the mechanism and the like are not particularly limited. The form of themixing process in the mixing unit 100 may be batch processing, or may beeither of a serial processing or continuous processing. The mixing unit100 may be operated manually or may be operated automatically. Althoughthe mixing unit 100 causes at least the fibrous material and thecomposite to be mixed together, other components may also be mixedtogether.

It is possible to give mechanical mixing or fluid dynamic mixing as anexample of the mixing process in the mixing unit 100. Examples of themechanical mixing include methods of introducing the fibers (fibrousmaterial) and the composite into a Henschel mixer, a blower or the likeand agitating with rotating blades, and methods sealing the fibers(fibrous material) and the composite in a bag and shaking the bag.Examples of the fluid dynamic mixing process include methods ofintroducing the fibers (fibrous material) and the composite in anairflow of the atmosphere or the like and diffusing the fibers (fibrousmaterial) and the composite into one another in the airflow. In themethod of introducing the fibers (fibrous material) and the composite inan airflow of the atmosphere or the like, the composite may be fed intoa pipe or the like in which the fibers of the fibrous material flow(transfer) by the airflow, or the fibers (fibrous material) may be fedinto a pipe or the like in which the particles of the composite flow(transfer) by the airflow. In this method, this is more preferablebecause the airflow in the pipe or the like being turbulent makes themixing together efficient.

The mixing unit 100 is provided on the upstream side of a bonding unit200, described later, in the flow direction of (a portion of) the rawmaterial in the sheet manufacturing apparatus 1000. Other configurationsmay be included between the mixing unit 100 and the bonding unit 200.Examples of such other configurations include a forming unit that formsthe mixture of the mixed fibers (fibrous material) and the compositeinto a web shape. The mixture (below, may be referred to as “mixedmaterial”) mixed together by the mixing unit 100 may be further mixed byanother configuration such as a sheet forming unit.

As shown in FIG. 1, as the mixing unit 100, in a case of employing thepipe 86 as described above for the transfer of the fibers, there aremethods of introducing the composite a state in which the fibers arecaused to flow by the airflow of the atmosphere or the like. Examples ofthe generator of the airflow in the case of employing the pipe 86 in themixing unit 100 include a blower, not shown, and, as long as the abovefunctions are obtained, it is possible to use any generator, asappropriate.

Although it is possible the introduction of the composite in the case ofemploying the pipe 86 in the mixing unit 100 to be performed by theopening and closing operation of a valve or the hand of a user, it ispossible for the introduction to be performed using a screw feeder or adisk feeder, not shown, or the like as the composite supplying unit 150shown in FIGS. 1 and 2. Because it is possible to reduce thefluctuations in the content (addition amount) of the composite in theflow direction of the airflow by using these feeders, this is morepreferable. The same also applies in a case of transferring thecomposite with the airflow and introducing the fibrous material to theairflow.

In the sheet manufacturing apparatus 1000 of the embodiment, it ispreferable to select a dry-type form of the mixing unit 100. Here, thewording “dry-type” in the mixing refers to the state of being mixedtogether in air rather than in water. That is, the mixing unit 100 mayfunction in the drying state, or may function in a state where a liquidpresent as an impurity or an intentionally added liquid is present. Inthe case of intentionally adding the liquid, it is preferable for theliquid to be added to an extent that the energy and time for removingthe liquid through heat or the like do not increase excessively in laterprocesses.

1.2. Bonding Unit

The sheet manufacturing apparatus 1000 according to the embodiment isprovided with a bonding unit 200. The bonding unit 200 is installedfurther to the downstream side in the flow of the raw material than atleast the above-described mixing unit 100.

The bonding unit 200 has a function of forming the fibers (fibrousmaterial) and the composite mixed together in the above-described mixingunit 100, that is, a mixed material, into a predetermined shape. In theformed body (sheet) of the fibers and the composite formed in thebonding unit 200, a state in which the fibers and the composite arebonded is achieved.

In the specification, the wording “bonding the fibers and the composite”refers to a state in which the fibers and the composite are not easilyseparated, or a state in which the resin of the composite is arrangedbetween the fibers, and the fibers become difficult to separate via thecomposite. The wording “bonding” is the concept that includes bondingand includes a state in which two or more types of substance come intocontact and are not easily separated. The fibers may be parallel to orintersect one another when the fibers are bonded via the composite, or aplurality of fibers may be bonded to form one fiber.

In the bonding unit 200, the plurality of fibers is bonded via thecomposite by applying heat to the fibers and the composite mixedtogether in the mixing unit 100. In a case where resin that is oneconstituent component of the composite is a thermoplastic resin, whenheated to at least a temperature in the vicinity of the glass-transitiontemperature (softening point) or melting point (case of a crystallinepolymer), the resin softens or melts, and is fixed by the temperaturelowering. It is possible for the fibers and the composite to bond to oneanother by the fibers coming into contact so as to become entangled withthe resin softened, and the resin hardening. The fibers bond to eachother by other fibers bonding when solidified. In a case where the resinof the composite is a heat-curable resin, the resin may be heated to thetemperature of the softening point or higher, or may be heated to thecuring temperature (temperature at which the curing reaction arises) orhigher and it is possible to bond the fibers and the resin. It ispreferable that the melting point, the curing point, the curingtemperature and the like of the resin is lower than the melting point,the decomposition temperature, and the carbonization temperature of thefibers, and it is preferable that the type of both is combined andselected so as to have such a relationship.

In the bonding unit 200, pressure may be applied in addition to applyingheat to the mixed material, and in this case, the bonding unit 200includes a function of forming the mixed material into a predeterminedshape. Although the magnitude of the pressure applied is regulated, asappropriate, according to the type of sheet formed, and 50 kPa or moreto 30 MPa or less is possible. If the added pressure is low, a sheetwith a large porosity is obtained, and if high, a sheet with a lowporosity (high density) is obtained.

Examples of the specific configuration of the bonding unit 200 include,in addition to the heater roller 76 and the tension roller 77 as shownin FIGS. 1 and 2, a calender roller, a hot press molding machine, ahotplate, a hot air blower, an infrared heating device and a flashfixing device.

1.3. Other Configurations

The sheet manufacturing apparatus 1000 of the embodiment may include, asappropriate, a configuration for preprocessing, a configuration forintermediate processing, a configuration for post processing and thelike, in addition to the above-described mixing unit 100 and bondingunit 200. FIG. 2 schematically shows an example of the sheetmanufacturing apparatus 1000, and FIG. 3 shows an example of theconfiguration of the sheet manufacturing apparatus 1000.

Examples of the configurations for preprocessing that is a configurationthat performs processing of the fibers (fibrous material) or compositeintroduced to the mixing unit 100 include the crushing unit 10 (shredderor the like) that cuts the pulp sheet or waste paper or the like as araw material in air, the defibrating unit 20 that untangles the rawmaterial in air into a fiber form, the classifying unit 30 thatclassifies impurities (toner or paper strengthening agent) from thedefibrated material that is defibrated and the fibers (short fibers)shortened by the defibration in air, and the screening unit 40 thatscreens the long fibers (long fibers) from the defibrated material andthe undefibrated pieces that are insufficiently defibrated in air.Examples of the configuration for the intermediate processing that is aconfiguration for performing appropriate processing until the compositeand the fiber (mixed material) mixed by the mixing unit 100 areintroduced to the bonding unit 200 include the distribution unit 60 thatcauses the mixed material to descend while being dispersed in air, and asheet forming unit 70 that deposits the mixed material caused to descendfrom the distribution unit 60 and forms the mixed material into theshape of a web. The bonding unit 200 may be a portion of the sheetforming unit 70. Examples of the configuration for post processing thatis a configuration that performs processing on the sheet S formed by thebonding unit 200 include the drying unit 80 (FIG. 3) which causes thesheet S to be dried as necessary, a winding unit 90 that winds theformed sheet into a roll shape, a cutting unit 92 (FIG. 3) that cuts theformed sheet into a stipulated side, and a packaging unit 94 (FIG. 3)that packages the wound or cut sheet with a film or packaging paper.

It is possible for the sheet manufacturing apparatus 1000 of theembodiment to have configurations other than the configurations given asexamples above, and possible to have, as appropriate, a plurality ofconfigurations according to the purpose with the above-describedconfiguration included. The order of each configuration is not limited,and is able to be designed, appropriate, according to the purpose.

Below, a summary of each configuration will be described.

The crushing unit 10 cuts the raw material, such as the pulp sheet orfed sheet (for example, A4 sized waste paper) in air into small pieces.The shape and size of the small pieces, although not particularlylimited, is, for example, several cm squared. In the examples in thedrawings, the crushing unit 10 includes a crushing blade 11, and it ispossible for the fed raw materials to be cut by the crushing blade 11.An automatic feeding unit (not shown) for continuously feeding the rawmaterial may be provided in the crushing unit 10.

The small pieces cut by the crushing unit 10 are transported to thedefibrating unit 20 via the first conveyance unit 81 when received bythe hopper 15. The first conveyance unit 81 is communicated with theintroduction port 21 of the defibrating unit 20. The shape of the firstconveyance unit 81 and the second to sixth conveyance units 82 to 86,described later, is a pipe shape. In the example in the drawings, thesixth conveyance unit 86 configures a portion of the mixing unit 100,and shares a reference with the above-described pipe 86 because of beingthe same.

The defibrating unit 20 performs defibration treatment on the smallpieces (defibration object). The defibrating unit 20 generates fibrousuntangled fibers by subjecting the small pieces to defibrationtreatment.

Here, the wording “defibration treatment” refers to untangling the smallpieces in which the plurality of fibers is bonded into individualfibers. The material that passes through the defibrating unit 20 isreferred to as a “defibrated material”. There are also cases where resin(resin for causing a plurality of fibers to bond to one another)isolated from the fibers when the fibers are untangled, additives suchas blur-preventing agents and paper strengthening agents, and colorantssuch as ink and toner are included in the “defibrated material” inaddition to the untangled defibrated material fibers. In the descriptionthat follows, the wording “defibrated material” is at least a portion ofthe material passing through the defibrating unit 20, and may be mixedwith materials added after passing through the defibrating unit 20.

The defibrating unit 20 isolates the additives and the colorants fromthe fibers. The additives or colorants are discharged from the dischargeport 22 along with the defibrated material. The defibrating unit 20performs the defibration treatment on the small pieces introduced fromthe introduction port 21 by a rotary blade. The defibrating unit 20performs defibrating with a dry method in air.

The configuration of the defibrating unit 20 is not limited, andpossible examples include units that generate an airflow by a rotatorrotating, and defibrate the defibration object with the airflow. Thedefibrating unit 20 may include a mechanism that causes an airflow to begenerated. In this case, it is possible for the defibrating unit 20 tosuction the small pieces along with the airflow from an introductionport 21, perform the defibration treatment, and transport the rawmaterial to the discharge port 22 with the self generated airflow.

The defibrated material discharged from the discharge port 22 isintroduced to the classifying unit 30 via the second conveyance unit 82,as shown in FIG. 2. In a case of using a defibrating unit 20 notincluding an airflow generating mechanism, a mechanism that generates anair flow that introduces the small pieces to the introduction port 21may be separately provided on the upstream or downstream side of thedefibrating unit 20.

The classifying unit 30 isolates and removes the additives or colorantsfrom the defibrated material. An airflow classifier is used as theclassifying unit 30. The airflow classifier generates a swirlingairflow, and performs isolation according to the size and density of thematerials classified with centrifugal force, and it is possible toadjust the classification points through adjustment of the speed of theairflow and the centrifugal force. Specifically, a cyclone, an elbowjet, an eddy classifier and the like are used as the classifying unit30. In particular, it is possible for the cyclone to be favorably usedas the classifying unit 30 because the structure is simple. Below, acase of using a cyclone as the classifying unit 30 will be described.

The classifying unit 30 includes at least an introduction port 31, alower discharge port 34 provided on the lower portion, and an upperdischarge port 35 provided on the upper portion. In the classifying unit30, the airflow in which the defibrated material introduced from theintroduction port 31 is carried is caused to move circularly, and, in sodoing, centrifugal force is applied to the introduced defibratedmaterial, and the material is isolated into a first classified material(untangled fibers) and a second classified material (additive orcolorant) with a lower density than the first classified material. Thefirst classified material is used as the raw material of the sheet. Thesecond classified material is removed because of becoming a hindrancewhen forming the sheet. For example, the whiteness of the sheet when thesheet includes toner is lowered. The strength of the sheet whenmaterials smaller than the fibers are included is lowered. The firstclassified material is discharged from the lower discharge port 34 andis introduced to the introduction port 46 of the screening unit 40through the third conveyance unit 83. Meanwhile, the second classifiedmaterial is discharged to the outside of the classifying unit 30 fromthe upper discharge port 35 through the fourth conveyance unit 84. Inthis way, because the resin is discharged to the outside by theclassifying unit 30, even if the resin is supplied by the compositesupplying unit 150, described later, it is possible to prevent the resinfrom becoming surplus with respect to the defibrated material.

Although classifying the first classified material and the secondclassified material by the classifying unit 30 is disclosed, isolationis not always reliably performed. Comparatively small or less densematerials from the first classified material may be discharged to theoutside along with the second classified material. Comparatively highdensity materials or materials entangled with the first classifiedmaterial from the second classified material may be introduced to thescreening unit 40 along with the first classified material. In a case ofa pulp sheet without waste paper as the raw material, because materialscorresponding to the second classified material are not included, theclassifying unit 30 may be not provided as the sheet manufacturingapparatus 1000.

The screening unit 40 screens, in air, the defibrated material subjectedto defibration treatment into “passing-through material” that passesthrough the screening unit 40 and “residue” that does not pass through.A cylindrical sieve is used as the screening unit 40. The screening unit40 includes an introduction port 46 and a discharge port 47, as shown inFIG. 2. The screening unit 40 is a rotating sieve which large materialsthat are able to pass through the sieve pass through and large materialsthat are not able to pass through the first opening 42 do not passthrough. It is possible for the screening unit 40 to screen the shortfibers (passing-through material) according to a fixed length from thedefibrated material subjected to the defibrating treatment by the sieve.

The residue not passing through the sieve of the screening unit 40 isdischarged from the discharge port 47 and transported to the hopper 15via the fifth conveyance unit 85 as a return flow path, and is returnedagain to the defibrating unit 20, as shown in FIG. 1.

The passing-through material passing through the sieve of the screeningunit 40 is transported to the introduction port 66 of the distributionunit 60 via the sixth conveyance unit 86 (pipe 86) one received by thehopper 16. A supply port 151 for the composite (described later) thatcauses the fibers to bond to one another (defibrated materials to bondto one another) to be supplied is provided in the sixth conveyance unit86.

The composite supplying unit 150 supplied the composite in air from thesupply port 151 to the sixth conveyance unit 86 (pipe 86). That is, thecomposite supplying unit 150 supplies the composite to the path in whichthe passing-through material of the screening unit 40 moves from thescreening unit 40 to the distribution unit 60 (between the screeningunit 40 and the distribution unit 60). Although the composite supplyingunit 150 is not particularly limited as long as it is able to supply thecomposite to the sixth conveyance unit 86 (pipe 86), and a screw feeder,circle feeder and the like are used. The composite supplied from thecomposite supplying unit 150 will be described later.

As a result of the passing-through material and the composite of thescreening unit 40 passing through the sixth conveyance unit 86 (pipe86), the mixed material is formed until the distribution unit 60.Accordingly, in the sheet manufacturing apparatus 1000 of theembodiment, the mixing unit 100 is configured to include the compositesupplying unit 150 and the sixth conveyance unit 86 (pipe 86). The mixedmaterial may be further mixed in the distribution unit 60. Therefore,the distribution unit 60 may be a mixing unit 100.

The distribution unit 60 refines the entangled passing-through material.The distribution unit 60 may further refine the entangled composite in acase where the composite supplied from the composite supplying unit 150is fibrous. The distribution unit 60 evenly deposits the passing-throughmaterial and the composite on the deposition unit 72, described later.

A sieve is used as the distribution unit 60. The distribution unit 60 isa rotating sieve that is able to rotate due to a motor (not shown).

The distribution unit 60 includes an introduction port 66. Thedifference in terms of configuration between the distribution unit 60and the screening unit 40 is not including a discharge port (partcorresponding to the discharge port 47 of the screening unit 40).

The upper limit of the size of the openings in the sieve of thedistribution unit 60 is 5 mm. It is possible for materials to be refinedand pass through without lumps in which the fibers are entangled witheach other passing through by the size of the openings being 5 mm orless. Even if entangled fibers or the composite are present when mixedin the sixth conveyance unit 86, they are refined when passing throughthe distribution unit 60. Therefore, the fibers and the composite aredeposited on the deposition unit 72, described later, with a uniformthickness and density.

The wording “refine the entangled fibers” includes a case of completelyrefining the entangled fibers (case of all of the fibers reaching arefined state) and a case of refining a portion of the entangled fibersto the extent that the entangled fibers are able to pass through thesieve. The same applies to the meaning of the wording “refine theentangled composite”.

The wording “uniformly deposited” refers to a state of the depositedmaterial that is deposited being deposited at the same thickness and thesame density. However, because the all of the deposited material is notnecessarily manufactured as a sheet, the part that becomes the sheet maybe uniform.

The defibrated material and the composite passing through thedistribution unit 60 are deposited on the deposition unit 72 of thesheet forming unit 70. The sheet forming unit 70, as shown in FIGS. 1and 2, includes the deposition unit 72, the tension roller 74, theheater roller 76, the tension roller 77, and the winding roller 78. Thesheet forming unit 70 forms a sheet using the defibrated material andthe composite passing through the distribution unit 60. In the examplesin the drawings, the heater roller 76 and the tension roller 77 of thesheet forming unit 70 configure the above-described bonding unit 200.

The deposition unit 72 of the sheet forming unit 70 receives and causesthe defibrated material and the composite passing through thedistribution unit 60 to be deposited. The deposition unit 72 ispositioned below the distribution unit 60. Since the deposition unit 72receives the defibrated material and the composite, for example, thedeposition unit 72 is a mesh belt. The mesh tensioned by the tensionroller 74 is formed on the mesh belt. The deposition unit 72 movesthrough the tension roller 74 rotating. A web with a uniform thicknessis formed on the deposition unit 72 by the defibrated material and thecomposite from the distribution unit 60 continuously accumulating whilethe deposition unit 72 continuously moves.

The defibrated material and the composite deposited on the depositionunit 72 of the sheet forming unit 70 is heated and pressed by passingthrough the heater roller 76 according to the movement of the depositionunit 72. Due to the heat, the resin functions as a bonding agent andcauses the fibers to bond to each other, is thinned by the pressure, andthe sheet S is formed. The surface may be further smoothened by beingpassed through a calender roller, not shown. In the examples in thedrawings, the sheet S is wound onto the winding roller 78. Through theabove, it is possible to manufacture the sheet S.

2. FIBER

In the sheet manufacturing apparatus 1000 of the embodiment, the fibers(fibrous material) used as a portion of the raw material is notparticularly limited, and it is possible for a wide range of fibermaterials to be used. Examples of the fibers include natural fibers(animal or plant fibers) and chemical fibers (organic, inorganic ororganic-inorganic composite fibers), and more specifically, examplesinclude fibers made from cellulose, silk, wool, cotton, hemp, kenaf,flax, Ramie, jute, manila hemp, sisal hemp, softwood, and hardwood, andfibers made from rayon, lyocell, cupra, vinylon, acrylic, nylon, aramid,polyester, polyethylene, polypropylene, polyurethane, polyimide, carbon,glass, and metal and these may be used independently or mixed, asappropriate, or may be used as a regenerated fiber on which purificationor the like is performed. At least one of these fibers may be includedas the raw material. The fiber may be dried or may be contained or beimpregnated with a liquid such as water or an organic solvent. Varioussurface treatments may be performed. The material of the fibers may be apure material, or may be a material that includes various componentssuch as impurities, additives and other components.

The fibers used in the sheet manufacturing apparatus 1000 of theembodiment is string-like or ribbon-like, and may be one independentfiber or may be a plurality of fibers completely entangled with oneanother to form a string shape or a ribbon shape. The fibrous materialmay be formed in a cotton-like form, or may be a form in which aplurality of fibers may be partially physically or chemically bonded toone another. The structure of the fibers may be formed from one type ofmaterial, a so-called simple fiber, or the material may be continuouslyor step-wise modified from the center portion toward the outerperipheral portion. Examples of step-wise modifying the material fromthe central portion of the fiber toward the outer peripheral portioninclude a so-called core-sheath structure. The fibers may be in a linearform, may be in a curved form, or may further be in a curled formoverall. The shape of the cross-sectional of the fibers is notparticularly limited, and may be a circle, an ellipse, a polygon, or acombination thereof. The fibers may also be fibrillated fibers.

When the fibers used in the embodiment are made one independent fiber,the average diameter (in a case where the cross-section is not a circle,the diameter of a circle when a circle having the greatest length fromthe lengths in a direction perpendicular to the length direction orequivalent to the area of the cross-section (equivalent circle diameter)is assumed) thereof is 1 μm or more to 1000 μm or less, 2 μm or more to500 μm or less is preferable, and 3 μm or more to 200 μm or less is morepreferable.

Although the length of the fibers used by the sheet manufacturingapparatus 1000 of the embodiment is not particularly limited, in oneindependent fiber, the length along the length direction of the fiber is1 μm or more to 5 mm or less, 2 μm or more to 3 mm or less ispreferable, and 3 μm or more to 2 mm or less is more preferable. In acase where the length of the fibers is short, although the strength ofthe sheets may be insufficient because the fibers do not easily bondwith the composite, it is possible to obtain a sufficiently strong sheetas long as the length is within the above ranges. The length along thelength direction of the fibers may be the distance (length of thefibers) between both ends when both ends of one independent fiber isstretched so as not to break, as necessary, and placed in asubstantially linear state in this state. The average length of thefibers, as the length-length-weighted mean fiber length, is 20 μm ormore to 3600 μm or less, 200 μm or more to 2700 μm or less ispreferable, and 300 μm or more to 2300 μm or less is more preferable.The length of the fibers may have variations (distribution), and in acase where a normal distribution in a distribution obtained with an n of100 or more is assumed, the 8 for the length of one independent fibermay be 1 μm or more to 1100 μm or less, preferable 1 μm or more to 900μm or less, and more preferably 1 μm or more to 600 μm or less.

It is possible to measure the thickness and length of the fibers withvarious optical microscopes, scanning electron microscopes (SEM),transmission electron microscopes, fiber testers, or the like. In a caseof microscopic observation, cross-sectional observation and observationin a state where both ends of the one independent fiber are stretched soas to not be cut away, as necessary, can be performed by carrying outpretreatment, as appropriate, on the observation sample, as necessary.

In the specification, the wording “cotton-like” indicates a state ofhaving a three-dimensional bulky external shape due to one long fiber ora plurality of fibers being entangled with one another or comingpartially into contact with one another. That is, cotton-like indicatesa solid shape formed by entanglement or partial contact of the fibers,and a gas partially encapsulated in the shape. The phrasing cotton-likeis used regardless of whether or not the plurality of fibers are bondedto one another.

3. COMPOSITE OF RESIN AND COLORING AGENT

In the sheet manufacturing apparatus 1000 of the embodiment, thecomposite used as a portion of the raw material integrally includes aresin and a coloring material.

The state of the composite integrally including the resin and thecoloring material refers to a state where the resin or coloring materialfrom the composite do not easily break part (not easily drop off) ineither or both of the sheet manufacturing apparatus 1000 or themanufactured sheet S. That is, the state of the composite integrallyincluding the resin and the coloring material indicates a state in whichthe coloring materials are bonded to one another by the resin, a statewhere the coloring material is structurally (mechanically) fixed to theresin, a state where the resin and the coloring material are coagulateddue to electrostatic force or Van der Waal's forces, and a state inwhich the resin and the coloring material are chemically bonded. Thestate of the composite integrally including the resin and the coloringmaterial may also be a state where the coloring material is encapsulatedin the resin or may be a state where the coloring material is attachedto the resin, and includes a state where both states are present at thesame time. The same also applies to a case of integrally including theresin and the coagulation inhibitor, described later.

FIG. 4 schematically shows several states of cross-sections of thecomposite in which the resin and the coloring materials are integrallyincluded. Examples of the specific form of the composite integrallyincluding the resin and the coloring material include a composite 3having a structure in which a single or a plurality of coloringmaterials 2 is dispersed and encapsulated inside the resin 1 as shown inFIGS. 4(a) to 4(c), and a composite 3 in which a single or a pluralityof coloring materials 2 is attached to the surface of the resin 1 asshown in FIG. 4(d). In the sheet manufacturing apparatus 1000 of theembodiment, it is possible to use an aggregate (powder) of such acomposite 3 as the composite.

FIG. 4(a) shows an example of the composite 3 having a structure inwhich a plurality of coloring materials 2 (drawn as particles) isdispersed in the resin that configures the composite 3. Such a composite3 forms a so-called sea-island structure with the resin 1 dispersed as amatrix and the coloring material 2 as the domain. In the example,because of the state in which the coloring material 2 is surrounded bythe resin 1, it is difficult for the coloring material 2 to pass throughthe resin part (matrix) and be separate to outside the resin 1.Therefore, when various processes are received or when the sheet isformed in the sheet manufacturing apparatus 1000, the coloring material2 is in a state of not easily dropping off from the resin part. Thecoloring material 2 may come in contact with itself or the resin 1 maybe present between the coloring material 2 in the dispersion state thecoloring material 2 inside the composite 3 in this case. In FIG. 4(a),although the coloring material 2 is entirely dispersed, dispersion maybe biased toward one side. In the drawing, the coloring material 2 maybe only on the right side or the left side. As a coloring materialbiased to one side, the coloring material 2 may be arranged in thecenter portion of the resin 1 as in FIG. 4(b) or the coloring material 2may be arranged in a part near the surface of the resin 1 as in FIG.4(c). The resin 1 may include a mother particle 4 in the vicinity of thecenter and a shell 5 on the periphery thereof. The mother particle 4 andthe shell 5 may be the same type of resin as one another or may bediffering types of resin.

The example shown in FIG. 4(d) is the composite 3 with a form in whichthe coloring material 2 is embedded in the vicinity of the surface ofparticles formed from the resin 1. In the example, although the coloringmaterial 2 is exposed in the surface of the composite 3, it is possibleto attain a state in which the composite 3 does not easily fall off fromthe composite 3 through bonding (chemical or mechanical bonding) withthe resin 1 or mechanical fixing due to the resin 1, and to suitably usesuch a composite 3 in the sheet manufacturing apparatus 1000 of theembodiment as the composite integrally including the resin 1 and thecoloring material 2. In the example, the coloring material 2 may bepresent not only in the surface of the resin 1, but also on theinterior.

Although several forms of the composite integrally including the resinand the coloring material are given as examples, as long as the coloringmaterial does not easily drop off from the resin when various treatmentsare received in the sheet manufacturing apparatus 1000 or when the sheetis formed, there is no limitation to these forms, and a state in whichthe coloring material is attached by electrostatic force or Van derWaal's forces to the surface of the resin particles, the coloringmaterial does not easily fall off from the resin particles. It ispossible to adopt any form in which the coloring material does noteasily drop off from the composite even in a form in which theabove-described plurality of forms is combined with one another.

The coloring material includes a function making the color of the sheetS manufactured by the sheet manufacturing apparatus 1000 of theembodiment into a predetermined color. It is possible for a dye or apigment to be used as the coloring material, and in a case of integrallyincluding the resin in the composite, it is preferable to use a pigmentfrom the viewpoint of obtaining a better hiding power or chromagenicity.

The pigment, along with the color and type thereof is not particularlylimited, and it is possible to use various colors (such as white, blue,red, yellow, cyan, magenta, yellow, black, and special colors (pearl,metallic gloss)) of pigment used in ordinary inks. The pigment may be aninorganic pigment or may be an organic pigment. It is possible to useknown pigments disclosed in Japanese Unexamined Patent ApplicationPublication No. 2012-87309 or Japanese Unexamined Patent ApplicationPublication No. 2004-250559 as the pigment. White pigments and the likesuch as zinc oxide, titanium oxide, antimony white, zinc sulfide, grey,silica, white carbon, talc, alumina white may be used. These pigmentsmay be used either independently or mixed, as appropriate. In a case ofusing a white dye, it is more preferable to use a pigment formed from apowder that includes particles (pigment particles) with titanium oxideas a main component from the above-described examples on the point ofease of increasing the whiteness in the manufactured sheet S from themagnitude of the refractive index of the titanium oxide with a smallblending amount.

In the specification, the phrasing “coloring material” is used tosignify a material for coloring. In the specification, in a case of apigment, this includes the meaning of a powder in which a plurality ofsingle particles (pigment particles) thereof are aggregated. The wording“single particle (pigment particle)” refers to particles which aredifficult to make smaller than the above by an ordinary crushing unit.In the white pigment in which the material is titanium oxide, the singleparticle (pigment particle) may be fine crystals of titanium oxide asthe primary particles, and a plurality of primary particles may beaggregated. The coagulation between primary particles in this case mayaggregate when forming chemical bonds or twin crystals, a mechanicalcrushing is frequently difficult. The structure of one pigment particlemay be the particle itself or a bonded body of primary particles beingthe primary particle.

The method of integrally including the resin and the coloring materialto the composite is not particularly limited even in a case of adoptingthe structure of nay of the above-described FIGS. 4(a) to 4(d), and itis possible to use, as appropriate, known methods. An example of themethod of obtaining the composite of the form is described in theabove-described FIG. 2. Examples of the method of obtaining thecomposite of the form in FIG. 4(a) include a melt-kneading method ofheating a predetermined resin to the temperature of the softening pointor higher and kneading with the pigment (coloring material) and a methodof mixing the resin with the pigment while being dissolved or swelledwith water or a solvent. Examples of devices usable with these methodsinclude a kneader, a Banbury mixer, a single screw extruder, amulti-screw extruder, a twin roll, a triple roll, a continuous kneader,and a continuous twin roll. In a case of using these methods, thepigment may be subjected to a hydrophobization treatment in order forthe pigment to be more uniformly dispersed in the resin. In a case wherea coagulated mass of the pigment is present before the melt-kneading, itis effective to disperse the pigment uniformly in the resin by crushingthe coagulated mass with a mixer or the like.

It is possible to obtain the composite by pelletizing and crushing withan appropriate method after kneading. It is possible to perform thecrushing using a known crushing method. Examples of the crushing machineused include a hammer mill, a pin mill, a cutter mill, a pulverizer, aturbo mill, a disk mill, a screen mill, and a jet mill, and it ispossible to obtain the resin particles by combining these, asappropriate. The process of crushing may be performed stepwise, such asfinely crushing to a target particle diameter after first roughlycrushing so that the particle diameter becomes approximately 1 mm. Evenin such a case, it is possible to use the appropriate devices givenabove in each step. It is further possible to use a freeze-crushingmethod for improving the crushing efficiency of the composite. There arecases where the composite obtained in this way includes various sizes,and in order to make the composite into the target size, the compositemay be classified using a known classifying device. If the above methodsare adopted, it is possible to obtain a composite with the structure asshown in FIG. 4(a).

It is preferable for the content of the coloring material in thecomposite to be greater than 0% by mass to 50% by mass or less. Thecontent of the coloring material in the composite is greater than 0parts by weight to 100 parts by weight or less when expressed in termsof parts by weight (external addition: addition amount of the coloringmaterial to the resin). It is preferable that the content of thecoloring material in the composite is, from the viewpoints of obtainingsufficiently strong coloring of the manufactured sheet, of suppressingdropping off of the coloring material from the composite, and ofstability (suppressing brittle collapse of the composite due to impactor the like) of the shape of the composite, 1% by mass or more to 50% bymass or less, and 2% by mass or more to 30% by mass or less is morepreferable, and 3% by mass or more to 20% by mass or less is still morepreferable.

4. COMPOSITE OF RESIN AND COAGULATION INHIBITOR

A coagulation inhibitor may be blended into the composite or the powderthat includes the composite. The coagulation inhibitor, in a case ofbeing blended in the composite, has a function of making the compositeintegrally including the resin and the coloring material not coagulateto each other compared to a case of not being blended. Although variouscoagulation inhibitors can be used, in the sheet manufacturing apparatus1000 of the embodiment, it is preferable to use a type (may be coated(covered) or the like) arranged in the surface of the composite becauselittle to no water is used. When considering the coagulation inhibitioneffect, the composite may not integrally include the coloring materialor the coloring material may not be used. In the sheet manufacturingapparatus 1000 of the embodiment, the composite used as a portion of theraw material integrally includes a resin and a coagulation inhibitor.

Examples of the coagulation inhibitor include fine particles formed froman inorganic material, and it is possible to obtain an extremelysuperior coagulation inhibition effect by blending the particles in thesurface of the composite as in FIG. 4(d). Therefore, reference 2 in FIG.4(d) may be the coagulation inhibitor.

The wording “coagulation” indicates a state where the same or differenttypes of substance are present in physical contact due to electrostaticforce or Van der Waal's forces. In a case of a state of not coagulatingin the aggregate (for example, powder) of the plurality of substances,all of the substances that configure the aggregation being arrangedwhile discrete is not necessarily indicated. That is, a state in which aportion of the substance that configures the aggregation is coagulatedis also included in the state of not being coagulated, and the even ifthe content of such a coagulated substance is approximately 10% by massor less of the entire aggregation, and preferably approximately 5% bymass or less, this state is included in the “state of not beingcoagulated” in the aggregate of the plurality of substances. A casewhere, although the particles of the powder are in a state of beingpresent in contact with each other, cases where it is possible to putthe particles into a discrete state by adding sufficient outside forcethat the particles are not broken down, such as gentle agitation,dispersing due to an airflow, and freely dropping in a case where thepowder is bagged or the like are included in the state of not beingcoagulated.

Specific examples of the material of the coagulation inhibitor includesilica, titanium oxide, aluminum oxide, zinc oxide, cerium oxide,magnesium oxide, zirconium oxide, strontium titanate, barium titanate,and calcium carbonate. Although a portion of the material of thecoagulation inhibitor is the same material as the coloring material, thematerials differ in that the particle diameter of the coagulationinhibitor is smaller than the particle diameter of the coloringmaterial. Therefore, therefore, because the coagulation inhibitor doesnot greatly influence the tone of the manufactured sheet, in thespecification the coagulation inhibitor can be distinguished from theabove-described coloring material. However, when regulating the tone ofthe sheet, even if the particle diameter of the coagulation inhibitor issmall, because a slight effect of light scattering or the like arises,it is preferable for such an effect to be taken into consideration.

The average particle diameter (number average particle diameter) of thecoagulation inhibitor particles, although not particularly limited is0.001 to 1 μm, and more preferably 0.008 to 0.6 μm. Although thecoagulation inhibitor particles being the primary particles is normal inlight of being close to the category of so-called nanoparticles, and theparticle diameter being small, a plurality of primary particles may bebonded to form a higher order particle. If the particle diameter of thecoagulation inhibitor primary particles is within the above ranges, itis possible to favorable coat the surface of the composite, and possibleto impart a sufficient coagulation inhibition effect. When thecoagulation inhibitor is arranged in the surface of the composite, thecoagulation inhibitor is present between different composites and it ispossible to suppress coagulation. When the composite and the coagulationinhibitor are separate bodies, because the coagulation inhibitor is notlimited to being present between the different composites, and there ascases where the composites coagulate with each other.

It is possible to obtain the above effects if the addition amount in thecase of adding the coagulation inhibitor to the composite is made 0.1parts by weight or more to 5 parts by weight or less with respect to 100parts by weight of the composite, and from the viewpoint of either orboth of increasing the effect and suppressing dropping off the of thecoagulation inhibitor from the manufactured sheet, 0.2 parts by weightor more to 4 parts by weight or less with respect to 100 parts by weightof the composite is preferable, and 0.5 parts by weight or more to 3parts by weight or less is more preferable.

The method of arranging (coating) the coagulation inhibitor in thesurface of the composite is not particularly limited, and thecoagulation inhibitor may be arranged along with the resin and thecoloring materials when forming the composite by melt-kneading or thelike as described above. However, if done in this way, because thecoagulation inhibitor is largely arranged inside the composite, thecoagulation inhibition effect with respect to the addition amount of thecoagulation inhibitor is reduced. It is more preferable that thecoagulation inhibitor is arranged as much as possible in the surface ofthe composite based on the coagulation inhibiting mechanism. Althoughexamples of the form for arranging the coagulation inhibitor in thesurface of the composite include coating and covering, the entiresurface of the composite is not necessarily coated. Although thecoverage ratio may exceed 100%, when reaching approximately 300% ormore, because there are cases where the action of bonding the compositeand the fibers is impeded, an appropriate coverage ratio is selectedaccording to the situation.

Although various methods are considered as the method of arranging thecoagulation inhibitor in the surface of the composite, although it ispossible to exhibit the effect by simply mixing together both and beingattached to the surface only by electrostatic force or Van der Waal'sforces, the concern of dropping off remains. Therefore, a method offeeding and uniformly mixing the composite and the coagulation inhibitorin a mixer that rotates at high speed is preferable. It is possible touse a known device as such a device, and it is possible to performmixing using an FM mixer, a Henschel mixer, a super mixer, or the like.It is possible to arrange the particles of the coagulation inhibitorparticles in the surface of the composite by such a method. There arecases where at least a portion of the coagulation inhibitor particlesarranged by such a method are arranged in a state of biting into or astate of being embedded into the surface of the composite, and it ispossible to make the coagulation inhibitor particles more difficult todetach from the composite, and it is possible to stably exhibit thecoagulation inhibition effect. When such a method is used, it ispossible to easily realize the above-described arrangement in a systemincluded little to no water content. Even if particles that do not biteinto the composite are present, it is possible for such an effect to besufficiently obtained. It is possible for the states in which thecoagulation inhibitor particles bite into or are embedded in the surfaceof the composite to be verified by various electron microscopes.

If the proportion covered by the coagulation inhibitor in the compositesurface (area ratio: in the specification, may be referred to as thecoverage ratio) is 20% or more to 100% or less, it is possible to obtaina sufficient charging effect. It is possible to adjust the coverageratio by incorporating in a device such as an FM mixer. If the specificsurface area of the coagulation inhibitor and the composite is known, itis possible to perform regulation by the mass (weight) of each componentwhen incorporated. It is possible to measure the coverage ratio withvarious electron microscopes. In a case where the coagulation inhibitoris arranged in a form of being not easily detached from the composite,it is possible for the coagulation inhibitor to be integrally includedin the composite.

When the coagulation inhibitor is arranged in the composite, becausecoagulation of the composite is made extremely difficult to occur, it ispossible for the composite and the fibrous material to be more easilymixed together in the mixing unit 100. That is, when the coagulationinhibitor is arranged in the composite, it is possible for the compositeto be quickly diffused in a space and form an extremely uniform mixedmaterial.

Examples of the reason it is possible for the composite and the fibersto be extremely favorably mixed together due to agitation by aircurrents or a mixer due to the coagulation inhibitor include that thecomposite tends to be easier to charge with static electricity in a casewhere the coagulation inhibitor is arranged in the surface of thecomposite, and coagulation of the composite due to the staticelectricity is suppressed. According to the research by the inventors,the composite attached to the fibers by to the static electricitybecomes less easily detached from the fibers even in cases where amechanical impact or the like occurs. In light of this trend, in a casewhere the coagulation inhibitor is arranged in the composite, it isthought that once the composite is attached to the fibers, it is easilymade more difficult to detach, and it is thought that the fibers and thecomposite are quickly mixed together without using another special unitfor mixing the fibers and the composite. Attachment of the composite tothe fibers after becoming a mixed material is stabilized, and nodetachment phenomenon is observed in the composite.

5. GENERAL COMPOSITE

The composite may include other components in addition to theabove-described resin, coloring agent, and coagulation inhibitor.Examples of the other components include organic solvents, surfactants,preservative and fungicide agents, antioxidants, ultraviolet absorbingagents, and oxygen absorbing agents.

The type of resin that is a component of the composite of the coloringagent or the coagulation inhibitor may be either a natural resin or asynthetic resin, and may be either a thermoplastic resin or aheat-curable resin. In the sheet manufacturing apparatus 1000 of theembodiment, the resin that configures the composite is preferably asolid at room temperature, and is preferably a thermoplastic resin inconsideration of bonding the fibers due to heat in the bonding unit 200.

Examples of the natural resin include rosin, dammar, mastic, copal,amber, shellac, dragon's blood palm resin, sandarac, and colophony, andthese resins may be independent or mixed, as appropriate, and may bemodified as appropriate.

Examples of the heat-curable resin from the synthetic resins includeheat-curable resins such as phenol resins, epoxy resins, melamineresins, urea resins, unsaturated polyester resins, allkyd resins,polyurethane, and heat-curable polyimide resins.

Examples of the thermoplastic resin from the synthetic resins include ASresins, ABS resins, polypropylene, polyethylene, polyvinyl chloride,polystyrene, acrylic resins, polyester resins, polyethyleneterephthalate, polyphenylene ether, polybutylene terephthalate, nylon,polyamide, polycarbonate, polyacetal, polyphenylene sulfide, andpolyetherether ketone. These resins may be used independently or mixed,as appropriate. Copolymerization or modification may be performed, andexamples of such systems of resin include styrene resins, acrylicresins, styrene-acrylic copolymer resins, olefin based, polyvinylchloride resins, polyester resins, polyamide resins, polyurethaneresins, polyvinyl alcohol resins, vinyl ether resins, N-vinyl resins,and styrene-butadiene resins.

In the examples in FIG. 4, although either of the external shape of thecomposite is schematically shown as close to spherical, the externalshape of the composite is not particularly limited, and may be a shapesuch as disk-shaped and an irregular shape. However, it is morepreferable that the shape of the composite approach spherical as much aspossible because of the ease of being arranged between the fibers in themixing unit 100.

The volume average particle diameter d of the crushed compositeinfluences the dispersion situation of the composite in the formed sheetS. In a case where the amount of the composite arranged in the sheet isfixed, although the bonding force between the fibers in parts where thecomposite is arranged increases when the volume average particlediameter d of the composite is large, because the dispersion(distribution) of the composite in the sheet S surface is coarse andparts were the bonding force between the fibers are possible, thestrength as a sheet S lowers. On the other hand, in a case where theamount of the composite arranged in the sheet S is fixed, because thecomposite is easily uniformly dispersed (distributed) in the sheet Ssurface when the volume average particle diameter d of the composite issmall, the strength as a sheet S also improves.

Although such a suitable volume average particle diameter d depends onthe blending amount of the composite in the sheet S, in a case where theblending amount is 5% by mass or more to 70% by mass or less, it ispreferable that the volume average particle diameter d is 1 μm or moreto 100 μm or less, and 5 μm or more to 35 μm or less is more preferable.

The size (volume average particle diameter d) of the composite is ableto be adjusted according to the size (average diameter D) of the fibersthat configure the fibrous material. For the size (volume averageparticle diameter d) of the composite, from the viewpoint of moreuniformly mixing the fibers and the composite in the mixing unit 100, itis preferable that the volume average particle diameter d of thecomposite is smaller than the size (average diameter D) of the particlesthat configure the fibrous material.

Although the above-described fibers (fibrous material) and composite aremixed together in the mixing unit 100, it is possible for the mixingratio thereof to be regulated, as appropriate, according to thestrength, usage, or the like of the manufactured sheet S. If themanufactured sheet S is for business usage, such as copy paper, theproportion of the composite to the fibers is 5% by mass or more to 70%by mass or less, and from the viewpoints of obtaining favorable mixingin the mixing unit 100 and making the composite less easily influencedby gravity in a case where the mixture is formed in a sheet-shape, 5% bymass or more to 50% by mass of less is preferable.

6. ACTIONS AND EFFECTS

According to the sheet manufacturing apparatus 1000 of the embodiment,even in a state (dry type) with little liquid, it is possible tofavorably perform mixing of the fibers and the composite in the mixingunit 100. The composite integrally including a resin and a coloringmaterial is bonded to the fibers in the bonding unit 200. Since thecoloring material is easily held by the resin that bonds the fibers toeach other, it is possible to manufacture a sheet in which the coloringmaterial is not easily detached by the composite integrally includingthe resin and the coloring material.

In a case where the coagulation inhibitor is integrated with the resinto make the composite, it is possible to remarkable reduce coagulationof the composites to each other. When the composites coagulate with eachother, parts with little composite are possible by the compositegathering in one portion. In the parts with little composite, thebonding force between the fibers becomes low, and the strength as asheet S is insufficient. When it is possible to reduce the coagulationof the composites to each other, it is possible for the composite to beuniformly dispersed, to create a sheet S with a favorable strength. In acase where the coloring material is integrated with the composite, thecoloring material is also uniformly dispersed, and it is possible tocreate a sheet S in which the uniformity of the tone in the sheet S isfavorable (color unevenness is suppressed). In so doing, it is possiblefor the composite integrally including the fibrous material and thecoagulation inhibitor to be uniformly mixed by a dry method, withoutusing moist pulp molding. The dispersion of the resin also becomesfavorable, and manufacturing sheet S with excellent strength ispossible. By integrating the resin and the coloring material, a sheet Swith favorable tone can be manufactured. Since the composite integrallyincluding either or both of the coloring material and the coagulationinhibitor and the resin is uniformly mixed by being mixed with theresin, the effect is exhibited even just by mixing. Although it isdifficult whether mixing is uniform in the mixed state, it is easy toverify the strength or the uniformity of tone as a sheet S by bondingthe resin and the composite. In a case where the resin and the coloringmaterial and the resin and the coagulation inhibitor are separatebodies, it is probably that there may be cases where a part thereof (forexample, 10%) is integrated in the course of transport or usage.However, those integrated afterwards in this way are easily detached,and even if approximately 10% is integrated, the effect is notexhibited. In the present application, since the integrated composite issupplied and 70% or more of the coloring material or the coagulationinhibitor is integrated with the resin, the effects are exhibited.

By suitably adjusting the size of the fibers and particle diameter ofthe composite, there is no color unevenness, and detachment of thecomposite from the fibrous material is suppressed. In this way, it ispossible to provide a sheet S such as a web, with excellent storabilityand transportabilty.

According to the sheet manufacturing apparatus 1000 of the embodiment, asheet S can be manufactured with a method using little to no water, andplumbing facilities and the like at the manufacturing facility areunnecessary. According to the sheet manufacturing apparatus 1000 of theembodiment, achieving size reductions is particularly easy because thewater using parts become unnecessary. Therefore, it is possible toincrease degree of freedom in the installation location. According tothe sheet manufacturing apparatus 1000 of the embodiment, the energysuch as electric power for dewatering and drying is unnecessary, andmanufacturing a sheet S in a short time not obtained in the pulp moldingmethod while achieving in lowering costs.

7. SHEET MANUFACTURING METHOD

The sheet manufacturing method of the embodiment includes a step ofmixing together a composite integrally including fibers and a resin anda coloring material or a resin and a coagulation inhibitor, and abonding the fibers and the composite together. Because the fibers, theresin, the coloring material, and the composite are the same as thosedescribed in the above-described sheet manufacturing apparatus item,detailed description thereof will not be provided.

The sheet manufacturing method of the embodiment may include at leastone step selected from a group composed of a step for cutting a pulpsheet or waste paper as a raw material in air, a defibrating step ofdisentangling the raw material in air into a fibrous form, a classifyingstep of classifying, in air, impurities (toner or paper strengtheningagent) and fibers (short fibers) shortened by defibration from thedefibrated material that is defibrated, a screening step of screening,in air, long fibers and undefibrated pieces that are insufficientlydefibrated from the defibrated material, a dispersing step of causingthe mixture to descend while being dispersed in air, a forming step offorming the descended mixture in a web shape or the like while beingdeposited, a drying step of causing the sheet to be dried as necessary,a winding step of winding the formed sheet into a roll shape, a cuttingstep of cutting the formed sheet, and a packaging step of packaging themanufactured sheet. The details of these steps are the same as thosedescribed in the above-described sheet manufacturing apparatus, and thusdetailed description will not be repeated.

8. SHEET

The sheet S manufactured by the sheet manufacturing apparatus 1000 orthe sheet manufacturing method of the embodiment mainly indicates asheet in which at least the above-described fibers are the raw materialand formed into a sheet form. However, there is no limitation to a sheetform, and the shape may be a board form, web form, or a shape havingconcavities and convexities. The sheets in the specification can beclassified into paper and non-woven fabric. Paper includes forms inwhich pulp or waste paper as a raw material is formed in a sheet shape,and includes recording paper for the purpose of writing or printing,wallpaper, packaging paper, colored paper, image paper, Kent paper andthe like. Non-woven fabric is a product thicker than paper or with lowstrength, and includes ordinary non-woven fabrics, fiber boards, tissuepapers, kitchen papers, cleaners, filters, liquid absorbing materials,sound absorbers, shock absorbers, mats, and the like.

9. ACCOMMODATION CONTAINER

The accommodation container of the embodiment accommodates theabove-described composite in which the resin and the coagulationinhibitor are integrated, used mixed with the fibers.

The composite of the embodiment is supplied to the mixing unit 100according to the opening and closing of a feeder or valve. The compositeof the embodiment is supplied in a powdered state in appearance.Therefore, it is possible to configure the apparatus so that thecomposite is directly supplied to the mixing unit 100 through a pipe orthe like after being manufactured. However, according to theinstallation location of the apparatus, it is thought that the compositeis carried along a flow path as a commodity, and there are cases wheretransfer or storage is performed after the composite is manufactured.

The accommodation container of the embodiment includes an accommodationchamber that accommodates the composite, and it is possible for thecomposite to be accommodated in the accommodation chamber. That is, itis possible for the accommodation container of the embodiment to be acomposite cartridge, and it is possible to easily transport and storethe composite.

The shape of the accommodation container is not particularly limited,and it is possible for the shape to be made a cartridge shape suitableto the sheet manufacturing apparatus 1000. It is possible to form theaccommodation container with an ordinary polymer material. Theaccommodation container may also be a box-like robust form, or may be afilm- (bag) like flexible form. It is preferable that the material thatconfigures the accommodation container is configured from a materialwith a low glass-transition temperature or melting point compared to thematerial of the accommodated composite.

The accommodation chamber that accommodates the container is notparticularly limited as long as it is able accommodate and hold thecomposite. It is possible for the accommodation chamber to be formedfrom a film, a molded body, or the like. In a case where theaccommodation chamber is formed by a film, the accommodation containermay be formed including a molded body (housing) so as to accommodate thefilm that forms the accommodation chamber. The accommodation chamber maybe formed by a comparatively robust molded body.

The film or molded body that forms the accommodation chamber may beconfigured from a polymer, a metal deposition film, or the like, and mayhave a multilayer structure. In a case where the accommodation containeris formed by a plurality of members such as a film or molded body, fusedparts or bonded parts may be formed. In a case where the accommodatedcomposite (powder) is influenced, such as deterioration, due to contactwith the atmosphere, it is preferable that the film or molded body isformed from a material with little gas permeability. It is preferablethat the material of the part that contacts the accommodated compositefrom the materials of the film and molded body that configure theaccommodation chamber is stable with respect to the composite.

The shape and volume of the accommodation chamber is not particularlylimited. Although the composite is accommodated in the accommodationchamber, an inactive solid or gas may be accommodated in contrastthereto. The volume of the composite accommodated in the accommodationchamber is also not particularly limited.

The accommodation chamber may include a flow port that communicatesbetween the interior of the accommodation chamber and the exterior ofthe accommodation container, and is able to remove the composite to theoutside of the accommodation container. The accommodation chamber mayhave another flow path other than the flow port formed therein. Theother flow path may be configured by a release valve or the like. In acase of providing the release valve in the accommodation chamber,although the position at which the release valve is arranged is notparticularly limited, there are cases where providing the release valveis preferable because the composite is not easily discharged when thepressure is released to the atmosphere in cases where pressure and thelike is generated in the accommodation chamber when arranged on theopposite side to the direction in which gravity acts in the normalposture when transferred, transported, and used.

10. MODIFICATION AND OTHER PROVISIONS

Although the sheet manufacturing apparatus and sheet manufacturingmethod of the embodiment use no or only a small amount of water, it ispossible to manufacture the sheet while adding water, as appropriate,with the object of adjusting the moisture or the like, through sprayingor the like as necessary.

In the specification, the phrasing “uniform” indicates, in a case ofuniform dispersion or mixing, the relative positions where one componentis present with respect to the other component are even in the entiresystem or are the same or substantially equal in each part of the systemto one another in a substance able to define a component with two typesor more or two phases or more. Uniformity of coloring or uniformity oftone indicates an even concentration without tinting of the color whenthe sheet is seen in plan view. However, in the specification, althoughthe composite is uniformly dispersed and coloring uniformity improves byintegrating the coagulation inhibitor and the resin, and is notnecessarily limited to being even. Resin that is not integrated is alsoproduced in the step of integrally manufacturing the coagulationinhibitor and the resin. Although coagulation does not occur, the resinenters a state of being somewhat separated from itself. Therefore, evenif even, the distance of all of the resin is not the same and theconcentration is also not completely the same concentration. Whenmanufactured as a sheet, if in a range in which the tensile strength issatisfied, and if the apparent coloring uniformity is satisfied, theuniformity in the specification is achieved. In the specification,uniformity of coloring, uniformity of tone, and color unevenness areused with the same meaning.

In the specification, phrasing such as “uniform”, “same”, “evenintervals” or the like is used to indicate that density, distance,measurement or the like are the same. Although it is desirable thatthese are equal, because being made completely equal is difficult, thewording includes being shifted by the cumulative errors or variationswithout the values being equal.

In a case of mixing powder of the fibers and the resin, if in a state(wet type) in which water is present in the system, as in the relatedart, because coagulation of the resin (powder) by the action of thewater is suppressed, it is comparatively easy to obtain a mixture with afavorable uniformity or obtain a favorable paper. However, inmanufacturing a regenerated paper in the present, the technology ofconsistently manufacturing with a dry method from a waste paper toregenerated paper is not necessarily sufficiently established.

According to the research of the inventors, that there is difficulty inmaking the step of mixing the fibers and the resin particles a drymethod can be understood as one reason thereof. That is, when the fibersand the resin powder are simply mixed without any work in a dry method,in a case where the fibers and the resin powder are not sufficientlymixed and a paper is obtained while being formed (deposited) in a sheetform in this state, it can be understood that the dispersion of theresin in the paper surface is non-uniform, and thus a paper withinsufficient mechanical strength is formed. When the fibers and theresin particles are mixed in a dry method, it can be understood thatcoagulation of the resin particles easily occurs according tocoagulation forces such as Van der Waal's force, and that dispersioneasily becomes non-uniform.

11. EXAMPLES

Below, although the present disclosure will be further described by theexamples shown, the invention is not limited to the examples below.

11.1. Example 1 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

1700 parts of polyester resin (manufactured by Toyobo Co., Ltd, brandname “Vylon 220”, glass-transition temperature: 54° C., softening point:96° C.), and 300 parts of blue copper phthalocyanine (manufactured byToyo Color Co., Ltd., brand name Lionol Blue FG-7330) were processedwith a high speed mixer (manufactured by Nippon Coke & Engineering Co.,Ltd, brand name “FM-type mixer FM-10C”), and a resin-pigment mixture wasobtained. The resin-pigment mixture was supplied from the hopper of atwin screw kneading extruder (manufactured by Toshiba Machine Co., Ltd.,trade name “TEM-26SS”), melt-kneading was performed, and the result waspelletized to obtain tablets with a diameter of approximately 3 mm.Since there is no phenomenon of the resin detaching from the time ofpelletizing, it is determined that the resin and the coloring materialare integrated.

(Size Adjustment of Composite)

After the pellets obtained in the above manner were cooled to thevicinity of room temperature, crushing was performed until particleswith a diameter of 1 mm or less were obtained with a hammer mill(manufactured by Dalton Co., Ltd., brand name “Labomill LM-05”). Thecrushed particles were further crushed by a jet mill (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “PJM-80SP”), and a compositewith a maximum particle diameter or 40 μm or less was obtained. Thecrushed material of the composite was classified by an airflowclassifier (manufactured by Nippon Pneumatic Mfg. Co., Ltd., brand name“MDS-3”), and the volume average particle diameter d of the compositewas made 10 μm.

(2) Coating Composite with Coagulation Inhibitor

100 parts by weight of the uncoated composite and 1 part by weight ofultrafine particles of titanium dioxide (manufactured by Fuji TitaniumIndustry Co., Ltd., brand name “SST-30EHJ”) as the coagulation inhibitorwere fed into a blender (manufactured by Waring Labs, brand name “WaringBlender 7012”), and mixing was performed for 60 seconds at a rotationspeed of 15600 rpm. After leaving the composite (integrally includingthe resin and the coloring material) subjected to this processing tostand for 24 hours in a glass container, no coagulating of the compositeto form masses (blocking) was recognized, and the particulate statehaving liquidity was maintained. In light of this, it is recognized thata state where the coating was formed (integrally including the resin andthe coloring material) and there was no coagulation was maintained.

(3) Fiber

Powdered cellulose (Nippon Paper Industries Co., Ltd., brand name “KCFLOCK W-50S”) was used. The average diameter of the fibers was 19 μm(below, these fibers are denoted as X).

(4) Manufacturing of Mixed Material

5 parts by weight of the composite material integrally including theresin and the coloring material obtained with (2) above, and 20 parts byweight of the above fibers X were fed into a blender (manufactured byWaring Labs, brand name “Waring Blender 7012”), mixing was performed for7 seconds at a rotation speed of 3100 rpm, and the composite and thefibers were mixed to obtain the mixed material.

(5) Manufacturing of Sheet

40 parts by weight of the composite material obtained in (4) above wasfed to a metal sieve with an opening size of 0.6 mm and a diameter of200 mm and the composite material was deposited on a fluororesin-coatedaluminum desk with a diameter of 180 mm (plate thickness 1mm)(manufactured by Sumitomo Electric Fine Polymer, Inc., brand name“Sumiflon Coated Aluminum”) using an electric sieve shaker device(manufactured by Retsch Ltd., brand name “AS 200”).

At this time, a slight 2 parts by weight of the composite remained onthe metal sieve. Because the deposited composite material is in the formof a bulky line shape, the composite material was carried on a fluorinecoated aluminum plate with the same diameter, pressurized andcompressed. After the formed composite material was held for 60 secondswhile set on a hot press in a state of being interposed by the aluminumdisk, the composite material was drawn out from the pressing machinewhile the pressure was released and left until reaching roomtemperature. Thereafter, the sheet (paper) was obtained by removing thehot formed composite material from the aluminum disk.

11.2. Example 2 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

Pellets were obtained similarly to Example 1.

(Size Adjustment of Composite)

Up to obtaining the composite with a maximum particle diameter or 40 μmwas performed similarly to Example 1. The composite was classified by anairflow classifier (manufactured by Nippon Pneumatic Mfg. Co., Ltd.,brand name “MDS-3”), and the volume average particle diameter d of thecomposite was made 20 μm.

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

This was the same as Example 1.

(4) Manufacturing of Mixed Material

This was the same as Example 1.

(5) Manufacturing of Sheet

This was the same as Example 1.

11.3. Example 3 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

This was the same as Example 1 (10 μm).

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

Kraft paper (manufactured by Oji Materia Co., Ltd., brand name “OKUnbleached Kraft”) was cut into paper pieces with a width of 10 mm and alength of 30 mm and linear fibers were obtained by processing these in adry type pulp defibrating machine (manufactured by Kumagai Riki KogyoCo., Ltd., No. 2535) at room temperature. The linear fibers were spreadon a metal sieve with an opening size of 5 mm, and used with theundefibrated material mixed into the fibers removed. The fiber diameterof the fibers was 33 μm (below, these fibers are denoted as Y).

(4) Manufacturing of Mixed Material

5 parts by weight of the composite obtained with (2) above, and 20 partsby weight of the above fibers Y were fed into a blender (manufactured byWaring Labs, brand name “Waring Blender 7012”), mixing was performed for7 seconds at a rotation speed of 3100 rpm, and the composite and thefibers were mixed to obtain the mixed material.

(5) Manufacturing of Sheet

40 parts by weight of the mixed material obtained in (4) above was fedto a metal sieve with an opening size of 3 mm and a diameter of 200 mand the composite material was deposited on a fluororesin-coatedaluminum desk with a diameter of 180 mm (plate thickness of 1mm)(manufactured by Sumitomo Electric Fine Polymer, Inc., brand name“Sumiflon Coated Aluminum”) using an electric sieve shaker device(manufactured by Retsch Ltd., brand name “AS 200”). At this time, aslight 2 parts by weight of the composite remained on the metal sieve.Because the deposited mixed material is in the form of a bulky lineshape, the composite material was carried on a fluorine coated aluminumplate with the same diameter, pressurized and compressed. After themixed material was held for 60 seconds while set on a hot press in astate of being interposed by the aluminum disk, the composite materialwas drawn out from the pressing machine while the pressure was releasedand left until reaching room temperature. Thereafter, the sheet (paper)was obtained by removing the hot formed composite material from thealuminum disk.

11.4. Example 4 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

This was the same as Example 2. (20 μm).

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

This was the same as Example 3.

(4) Manufacturing of Mixed Material

This was the same as Example 3.

(5) Manufacturing of Sheet

This was the same as Example 3.

11.5. Example 5 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

After the pellets obtained in similarly to Example 1 were cooled to thevicinity of room temperature, crushing was performed until particleswith a diameter of 1 mm or less were obtained with a hammer mill(manufactured by Dalton Co., Ltd., brand name “Labomill LM-05”). Thecrushed particles were further crushed by a jet mill (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “PJM-80SP”), and a compositewith a maximum particle diameter or 60 μm or less was obtained. Thecomposite was classified by an airflow classifier (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “MDS-3”), and a composite inwhich the resin and the coloring material are integrated with volumeaverage particle diameter d of 35 μm was obtained.

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

This was the same as Example 3.

(4) Manufacturing of Mixed Material

This was the same as Example 3.

(5) Manufacturing of Sheet

This was the same as Example 3.

11.6. Example 6 (1) Structure of Composite Integrally Including Resinand Coloring Material (Integration of Coloring Material to Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

After the pellets obtained similarly to Example 1 were cooled to thevicinity of room temperature, crushing was performed until particleswith a diameter of 1 mm or less were obtained with a hammer mill(manufactured by Dalton Co., Ltd., brand name “Labomill LM-05”). Thecrushed particles were further crushed by a jet mill (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “PJM-80SP”), and a compositewith a maximum particle diameter or 25 μm or less was obtained. Thecomposite was classified by an airflow classifier (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “MDS-3”), and a composite inwhich the resin and the coloring material are integrated with volumeaverage particle diameter d of 5 μm was obtained.

(2) Coating Composite with Coagulation Inhibitor

100 parts by weight of the uncoated composite obtained in (1) above and2.5 parts by weight of ultrafine particles of titanium dioxide(manufactured by Fuji Titanium Industry Co., Ltd., brand name“SST-30EHJ”) as the coagulation inhibitor were fed into a blender(manufactured by Waring Labs, brand name “Waring Blender 7012”), mixingwas performed for 30 seconds at a rotation speed of 15600 rpm, theresult was left for 120 seconds, and then further mixing was performedfor 30 seconds at the same rotation speed. After leaving the compositesubjected to this processing to stand for 24 hours in a glass container,no coagulating of the composite (powder) to form masses (blocking) wasrecognized, and, the particulate state having liquidity was maintained.In light of this, it is recognized that a state where the coating wasformed (integrally including the resin and the coloring material) andthere was no coagulation was maintained.

(3) Fiber

This was the same as Example 1.

(4) Manufacturing of Mixed Material

This was the same as Example 1.

(5) Manufacturing of Sheet

This was the same as Example 1.

11.7. Reference Example 1 (1) Structure of Composite IntegrallyIncluding Resin and Coloring Material (Integration of Coloring Materialto Resin)

This was not carried out.

(Size Adjustment of Resin Particles)

In this example, the composite was not used, and resin particles notintegrally including the coloring material were used. 2000 parts(pellets) of polyester resin (manufactured by Toyobo Co., Ltd, brandname “Vylon 220”) were roughly crushed until the diameter reached a sizeof 1 mm or less with a hammer mill (manufactured by Dalton Co., Ltd,brand name “Labomill LM-05”). The resin particle powder was furthercrushed by a jet mill (manufactured by Nippon Pneumatic Mfg. Co., Ltd.,brand name “PJM-80SP”), and a particulate with a maximum particlediameter or 40 μm or less was obtained. The obtained particulate wasspread on a metal sieve with 100 μm openings and foreign materials andcoarse particles were removed. The particulate was classified by anairflow classifier (manufactured by Nippon Pneumatic Mfg. Co., Ltd.,brand name “MDS-3”), and a resin particles with volume average particlediameter d of 10 μm was obtained.

(2) Coating Resin Particles with Coagulation Inhibitor(Coating Resin Particles with Coagulation Inhibitor)

This was not carried out.

(3) Fiber

This was the same as Example 1.

(4) Manufacturing of Mixed Material

0.75 parts by weight of blue copper phthalocyanine (manufactured by ToyoColor Co., Ltd., brand name Lionol Blue FG-7330), 4.75 parts by weightof the resin particles obtained in (1) above, 0.05 parts by weightultrafine particles of titanium dioxide (manufactured by Fuji TitaniumIndustry Co., Ltd., brand name “SST-30EHJ”), and 20 parts by weight ofthe fibers X in (3) above were fed into a blender (manufactured byWaring Labs, brand name “Waring Blender 7012”), mixed for 7 seconds at arotation speed of 3100 rpm, to obtain the mixed materials (resin andcoloring material become separate bodies) formed from the fibers, theresin particles, the pigment (coloring material), and the coagulationinhibitor.

(5) Manufacturing of Sheet

This was the same as Example 1.

11.8. Reference Example 2 (1) Structure of Composite IntegrallyIncluding Resin and Coloring Material (Integration of Coloring Materialto Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

After the pellets obtained similarly to Example 1 were cooled to thevicinity of room temperature, crushing was performed until particleswith a diameter of 1 mm or less were obtained with a hammer mill(manufactured by Dalton Co., Ltd., brand name “Labomill LM-05”). Thepowder (particulate) was further crushed by a jet mill (manufactured byNippon Pneumatic Mfg. Co., Ltd., brand name “PJM-80SP”), and a compositewith a maximum particle diameter or 70 μm or less was obtained. Theobtained composite was spread on a metal sieve with 100 μm openings andforeign materials and coarse particles were removed. The composite wasclassified by an airflow classifier (manufactured by Nippon PneumaticMfg. Co., Ltd., brand name “MDS-3”), and a composite in which the resinand the coloring material are integrated with volume average particlediameter d of 50 μm was obtained.

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

This was the same as Example 1.

(4) Manufacturing of Mixed Material

This was the same as Example 1.

(5) Manufacturing of Sheet

This was the same as Example 1.

11.9. Reference Example 3 (1) Structure of Composite IntegrallyIncluding Resin and Coloring Material (Integration of Coloring Materialto Resin)

This was the same as Example 1.

(Size Adjustment of Composite)

After the pellets obtained similarly to Example 1 were cooled to thevicinity of room temperature, the pellets were introduced to a hammermill (manufactured by Dalton Co., Ltd., brand name “Labomill LM-05”) andcrushing was performed until particles with a diameter of 1 mm or lesswere obtained. The crushed product was further crushed by a dry-typecrusher (manufactured by Sugino Machine Limited, brand name “Dry BurstDB-180W”), and a composite (particulate) with a maximum particlediameter of 130 μm or less was obtained. The obtained composite wasspread on a metal sieve with 400 μm openings and foreign materials andcoarse particles were removed. The composite was classified by anairflow classifier (manufactured by Nippon Pneumatic Mfg. Co., Ltd.,brand name “MDS-3”), and a composite (with the resin and the coloringmaterial integrated) with volume average particle diameter d of 80 μmwas obtained.

(2) Coating Composite with Coagulation Inhibitor

This was the same as Example 1.

(3) Fiber

This was the same as Example 3.

(4) Manufacturing of Mixed Material

This was the same as Example 1.

(5) Manufacturing of Sheet

This was the same as Example 3.

11.10. Reference Example 4 (1) Structure of Composite IntegrallyIncluding Resin and Coloring Material (Integration of Coloring Materialto Resin)

This was not carried out.

(Size Adjustment of Resin Particles)

Other than not using the composite, and using resin particles to whichthe coloring material is not integrated, Reference Example 4 was carriedout similarly to Reference Example 2, and a particulate with a volumeaverage particle diameter d of 50 μm.

(2) Coating Resin Particles with Coagulation Inhibitor(Coating Resin Particles with Coagulation Inhibitor)

This was not carried out.

(3) Fiber

This was the same as Example 1.

(4) Manufacturing of Mixed Material

0.75 parts by weight of blue copper phthalocyanine (manufactured by ToyoColor Co., Ltd., brand name Lionol Blue FG-7330) 4.75 parts by weight ofthe resin particles obtained in (1) above, and 20 parts by weight of thefibers X were fed into a blender (manufactured by Waring Labs, brandname “Waring Blender 7012”) and mixed for 7 seconds at a rotation speedof 3100 rpm, to obtain the mixed material (resin particles and coloringmaterial become separate bodies) formed from the fibers, the resinparticles, the pigment (coloring material), and the coagulationinhibitor.

(5) Manufacturing of Sheet

This was the same as Example 1.

11.11. Measurement and Evaluation Methods (Measurement Method ofParticle Diameter)

Measurement of the particle diameter of the composite or the resinparticles was performed suspended in water with a wet-type flow-typeparticle size and particle shape analyzer (manufactured by SysmexCorporation, brand name “FPIA-2000”). The results thereof are recordedin Table 1. When the composite or the resin particles are suspended, 2parts by weight of surfactant (manufactured by Kao Corporation, brandname “Emulgen 120”) with respect to 100 parts by weight of thesuspension liquid were added and subjected to ultrasound treatment forone minute and a state where coagulation of the suspension liquid wasresolved was obtained.

(Measurement Method of Fiber Diameter in Fibrous Material)

Measurement of the fiber diameter of the fibrous material was carriedout with the fibers suspended in water by a fiber tester (manufacturedby Lorentzen & Wettre, “FiberTester”). The average diameter D of theobtained fibers is disclosed in Table 1.

(Relationship Between Volume Average Particle Diameter d of Composite orResin Particles and Average Diameter D of Fibers in Mixed Material)

For the value of the relationship between the volume average particlediameter d of the composite or the resin particles and the averagediameter D of the fibers in the mixed material, the value of d/D andwhether or not the relationship of d≤D is satisfied, with a case wheresatisfied as “◯”, a case where not satisfied as “x”, and a case wheresatisfied in a range of ±10% of the value as “Δ” are disclosed in Table1.

(Measurement Method of Tensile Strength of Sheet)

After a test piece (total length 75 mm) of 1BA of JISK 7162 was cut outfrom the sheet (paper) obtained with the above-described method, andtensile testing was carried out. Compliant with JISK 7161, testing wasperformed in an environment of a 23° C. room temperature and a relativehumidity of 50%. The strength (MPa) value of the breaking point in eachexample is disclosed in Table 1.

(Evaluation Method of Coloring Uniformity of Sheet (Paper))

A test piece with a width of 15 mm and a length of 120 mm was cut outfrom a sheet (paper) obtained by the above methods, and the opticalreflection density at positions of 20 mm, 40 mm, 60 mm, 80 mm, and 100mm from the end portion was measured with a spectral densiometer(manufactured by Xrite Incorporated, brand name “X-Rite 528”) in cyanmode. When maximum value of the optical reflection density is A and theminimum value is B at this time, the value of C=100×(A−B)/A (%) being 5%or less was determined to be “◯” (no color unevenness), a case of morethan 5% to 10% or less to be “Δ”, and a case where greater than 10% tobe “x” (color unevenness present).

(Evaluation Method of Coloring Material Detachment in Sheet (Paper))

The paper was moved while the sheet (paper) obtained with theabove-described methods was pinched to a pinching body with a pressureof 981 Pa. Cases where the coloring material attached to the pinchingbody are recorded as “x” (detachment present, not acceptable) in Table1, and cases where not attached as “◯” (no detachment, no problem). Thismay serve as an evaluation of whether the coloring material attached toa finger when the paper is rubbed with the finger.

(Quality Determination of Sheet (Paper))

Functional testing for the sheet (paper) obtained with each example wasperformed. The tactile sensation, feel, and external appearance of thepaper of each example was verified by 20 men and women of the ages of 20to 50, and cases where 15 or more determined that the paper couldwithstand use as a paper are disclosed in Table 1 as “0” and cases wherenot determined as “x”.

11.12. Experimental Results

The characteristics of the samples, type of fibrous material, fiberdiameter of the fibrous material, configuration of the composite orresin particles, tensile strength of the sheet (paper), detachment ofthe coloring material in the sheet (paper), coloring uniformity of thesheet (paper), and quality evaluation results for each example and eachreference example are summarized in Table 1.

TABLE 1 Composite Fibrous Material Volume Average Form of Form ofAverage Mixed Material Sheet Particle Diameter Integration Integrationof Diameter D Value Deter- Tensile Coloring Detachment Quality d (μm) ofof Colored Coagulation (μm) of of mination Strength Unifor- of ColoredDeter- Composite Material Inhibitor Type Fibers d/D of d ≤ D (MPa) mityMaterial mination Example 1 10 Integrated Integrated Fibers X 19 0.53 ◯41 ◯ ◯ ◯ Example 2 20 Integrated Integrated Fibers X 19 1.05 Δ 39 ◯ ◯ ◯Example 3 10 Integrated Integrated Fibers Y 33 0.30 ◯ 61 ◯ ◯ ◯ Example 420 Integrated Integrated Fibers Y 33 0.61 ◯ 62 ◯ ◯ ◯ Example 5 35Integrated Integrated Fibers Y 33 1.06 Δ 52 ◯ ◯ ◯ Example 6  5Integrated Integrated Fibers X 19 0.26 ◯ 39 ◯ ◯ ◯ Reference 10 SeparateSeparate Fibers X 19 0.53 ◯ 10 x x x Example 1 Reference 50 IntegratedIntegrated Fibers X 19 2.63 x 11 ◯ ◯ x Example 2 Reference 80 IntegratedIntegrated Fibers Y 33 2.42 x 19 ◯ ◯ x Example 3 Reference 50 SeparateNot added Fibers X 19 2.63 x  9 x x x Example 4

In Reference Examples 1 and 4 in which the composite not integrallyincluding the resin and the coloring material, that is a mixture inwhich the resin and the coloring material are separate bodies,detachment of the coloring material was observed. In contrast, in eachof the other examples in which the composite integrally including theresin and the coloring material, detachment of the coloring material wasnot observed. It is recognized that there was almost no detachmentbecause the coloring material is bonded to the fibers via the resin bythe composite integrally including the resin and the coloring material.Meanwhile, in a case where the resin and the coloring material aresimply mixed together, because the coloring material is bonded to thefibers without the resin, it is recognized that the coloring materialdetaches with a pressure approximating rubbing with a finger.

The coloring uniformity was favorable for Examples 1 to 6 using thecomposite integrally including the resin and the coagulation inhibitor.This is because coagulation of the composite is suppressed, and thecomposite is uniformly dispersed by using the composite in which theresin is integrated by being coating with the coagulation inhibitor. Inlight of this, it can be said that when the resin and the coagulationinhibitor are integrated, an effect is exhibited in which the resin isuniformly dispersed.

The tensile strength of the sheet was more favorable for Examples 1 to 6using the composite integrally including the resin and the coagulationinhibitor than in the Reference Example 2 in which the resin and thecoagulation inhibitor are separate bodies. This is because, although thecoagulation inhibition effect is present in a case where the resin andthe coagulation inhibitor are separate bodies and in a case where thecoagulation inhibitor is arranged between the resin, the resincoagulates with the resin in a case where there is no coagulationinhibitor between the resin, and the resin is not uniformly dispersed.Therefore, locations where the fibers are not bonded to the fibers bythe resin, and the strength as a sheet is lowered. Meanwhile, the resinis uniformly dispersed when the resin and the coagulation inhibitor areintegrated, favorable values are achieved without lowering the strengthas a sheet.

It was determined from Reference Examples 2 to 4 that when d/D greatlyexceeds one, the tensile strength degrades. This is because when thediameter of the composite is large, the amount of composite (number ofparticles) is reduced when the same weight of composite is mixed withthe fibers, and the number of composite particles bonding the fibers tothe fibers is reduced. It is thought that the composite not easilyentering between fibers due to the diameter of the composite being largealso contributes. Although d/D in Reference Examples 2 and 5 slightlyexceeds one, the tensile strength does not degrade. Therefore, it can besaid that there are no problems of tensile strength if d/D is one orless. Because d/D is one or less, the size of the composite becomes thethickness of the fibers or less. In light of the results of Examples 1,3, 4, and 6, it is recognized that there is no problem even if thediameter of the fibers or the resin is changed if d≤D is satisfied. Inlight of the results of Example 6, it is preferable that d/D is 0.26 ormore, and in light of the results of Example 3, 0.30 or more is morepreferable.

As is evident from Table 1, it is determined that the coloring material(pigment) being integrated with the composite, and the composite beingcoated with the coagulation inhibitor (coagulation inhibitor is alsointegrated with the composite) are extremely effective in order toresolve detachment of the coloring material (pigment) from the mixedmaterial in a case of adding the coloring material (pigment) in order tocolor the mixed material. It is thought that this is because thecomposite and the coloring material are dispersed in the same way, andit is understood that this is also effective is a wet-method.

In methods (external addition) of mixing the coagulation inhibitor,fibers and composite together that are not integrated with respect tothe composite (separate), because the effect of suppressing coagulationof the composite is reduced and not resolved when the coagulation of thecomposite is not resolved, it is recognized that sufficiently uniformlymixing the fibers and the composite is difficult.

In contrast, after the composite is coated (integrated) with thecoagulation inhibitor, it was determined that a mixed material and sheetwith superior coloring uniformity was obtained by mixing with thefibers. That is, it is recognized that it is effective to integrate thepigment (coloring material) for the composite in order to reduce thecolor unevenness of the mixed material and the sheet and to increase thecolor uniformity. There is also an effect of being easily dispersedbetween fibers by the composite being a powder rather than sheath-like.

As is evident from Table 1, it is recognized that the obtained sheet(paper) has the characteristics of superior uniformity of coloring(uniformity of tone) after formation and superior tensile strength byforming the sheet using the mixed material in which the compositeintegrally including either or both of the coloring agent and thecoagulation inhibitor with the resin and the fibers. In order to obtainsuch a sheet (paper), it is understood that it is extremely effective toform the sheet with the composite integrally including the pigment andthe coagulation inhibitor integrated into the composite, and using amixed material in which the relationship “volume average particlediameter d of composite average diameter D of fiber” is satisfied.

The present disclosure is not limited to the embodiments describedabove, and further, various modifications thereof are possible. Forexample, the invention includes configurations which are substantiallythe same as the configurations described in the embodiments (forexample, configurations having the same function, method, and results,or configurations having the same purpose and effect). The inventionincludes configurations in which non-essential parts of theconfigurations described in the embodiments are replaced. The inventionincludes configurations exhibiting the same actions and effects as theconfigurations described in the embodiments or configurations capable ofachieving the same object. The invention includes configurations inwhich known techniques were added to the configurations described in theembodiments.

The invention is suitable to a sheet in which a tensile strength of 39MPa or more is demanded. Generally, a higher value of tensile strengthis demanded for a paper than for a non-woven fabric. This is because itis a cause of breakdown when used in a printer or the like. Therefore,since the paper is more suitable than a non-woven fabric, the sheet maybe replaced with a paper. However, it is not problematic if thenon-woven fabric is used.

According to an aspect, there is provided a sheet manufacturingapparatus including a mixing unit in which fibers and a compositeintegrally including a resin and a coloring material are mixed, and abonding unit that bonds the fibers and the composite.

According to such a sheet manufacturing apparatus, the compositeintegrally includes a coloring material and a resin and thus thecoloring material is not easily detached from the composite. Since thecomposite and the fibers are bonded, the coloring material is also noteasily detached from the fibers. Therefore, it is possible tomanufacture a sheet in which color unevenness is suppressed.

In the sheet manufacturing apparatus according to the aspect, thecomposite may further integrally include a coagulation inhibitor.

According to such a sheet manufacturing apparatus, since the compositealso integrally includes a coagulation inhibitor, it is possible tosuppress coagulation of the composite in the vicinity. In a case wherethe composite includes the coagulation inhibitor as a separate body, thecoagulation inhibition effect is not exhibited if the coagulationinhibitor is not present between the composite and another composite, incontrast, because the coagulation inhibitor is integrally included ifthe composite according to the aspect is used, it is possible toreliably exhibit the coagulation inhibition effect. Therefore, becauseit is possible for the composite to be dispersed and mixed with respectto the fibers in the mixing unit, and more uniform mixing is performed,it is possible to manufacture a sheet with higher mechanical strength,and more favorable uniformity of the tone.

In the sheet manufacturing apparatus according to the aspect, thecomposite may be a powder.

According to such a sheet manufacturing apparatus, since the compositeeasily enters between fibers because the composite is a powder comparedto another shape of composite, such as a sheath shape, in the mixingunit, a more uniform mixture is possible, and it is possible tomanufacture a sheet with higher mechanical strength and more favorableuniformity of the tone.

In the sheet manufacturing apparatus according to the aspect, the sizeof the composite may be the thickness of the fibers or less.

According to such a sheet manufacturing apparatus, because the size ofthe composite is the thickness of the fibers or less, the compositeeasily enters between the fibers in contrast to not easily enteringbetween the fibers when the size of the composite is larger than thethickness of the fibers, and because mixing is more uniformly performedin the mixing unit, it is possible to manufacture a sheet with highermechanical strength, and more favorable uniformity of the tone.

In the sheet manufacturing apparatus according to the aspect, thecoloring material may be encapsulated in the resin.

According to such a sheet manufacturing apparatus, because the coloringmaterial is positioned further to the inside than the surface of theresin, the coloring material does not easily drop off from the resineven by friction such as rubbing the manufactured sheet with a finger,and it is possible to manufacture a favorable sheet with a more uniformtone.

According to another aspect of the invention, there is provided a sheetmanufacturing method including a step of mixing fibers and a compositeintegrally including a resin and a coloring material; and a step ofbonding the fibers and the composite.

According to such as sheet manufacturing method, since the coloringmaterial is easily held by the resin of the composite, it is possible tomanufacture a sheet in which the coloring material is not easilydetached.

According to still another aspect, there is provided a sheet including araw material including fibers and a composite integrally including aresin and a coloring material, in which the fibers and the composite arebonded.

Since the coloring material is held by the resin of the composite insuch a sheet, the coloring material is not easily detached.

According to still another aspect, there is provided an accommodationcontainer which accommodates a composite used to be mixed with thefibers and integrally including the resin and the coloring material.

It is possible for such an accommodation container to easily transportand hold the composite.

According to still another aspect, there is provided a compositeintegrally including a resin and a coloring material and used to bemixed with the fibers.

Since the coloring material is easily held by the resin when such acomposite is mixed with the fibers, the coloring material is not easilydetached.

According to still another aspect, there is provided a composite used ina sheet manufacturing apparatus and integrally including the resin andthe coloring material.

Since the coloring material is easily held by the resin in such acomposite, the coloring material is not easily detached from themanufactured sheet.

According to still another aspect, there is provided a sheetmanufacturing apparatus including a mixing unit in which fibers and acomposite integrally including a resin and a coagulation inhibitor aremixed, and a bonding unit that bonds the fibers and the composite.

According to such a sheet manufacturing apparatus, because the compositeintegrally includes the coagulation inhibitor and the resin, coagulationof the resin is suppressed. Therefore, the resin is dispersed in theentire sheet and it is possible to manufacture a high strength sheet.

In the sheet manufacturing apparatus, the composite may be a powder.

According to such a sheet manufacturing apparatus, because the compositeis a powder, compared to another shape of composite, such as a sheathshape, the composite easily enters between the fibers during mixing.Therefore, more uniform mixing is possible, and it is possible tomanufacture a high strength sheet.

According to still another aspect, there is provided a sheetmanufacturing method including a step of mixing fibers and a compositeintegrally including a resin and a coagulation inhibitor; and a step ofbonding the fibers and the composite.

According to such a sheet manufacturing method, the resin does noteasily coagulate due to the coagulation inhibitor integrated with theresin, and it is possible to manufacture a high strength sheet.

According to still another aspect, there is provided a sheet including araw material including fibers and a composite integrally including aresin and a coagulation inhibitor, in which the fibers and the compositeare bonded.

In such a sheet, the resin does not easily coagulate due to thecoagulation inhibitor integrated with the resin, and the strengthbecomes high.

According to still another aspect, there is provided an accommodationcontainer which accommodates a composite used mixed with fibers andintegrally including the resin and the coagulation inhibitor.

It is possible for such an accommodation container to easily transportand hold the composite.

According to still another aspect, there is provided a compositeintegrally including a resin and a coagulation inhibitor and used mixedwith the fibers.

Since the resin does not easily coagulate due to the integratedcoagulation inhibitor when such a composite is mixed with the fibers,the resin is easily dispersed with respect to the fibers.

According to still another aspect, there is provided a composite used ina sheet manufacturing apparatus and integrally including the resin andthe coagulation inhibitor.

Since the resin does not easily coagulate due to the integratedcoagulation inhibitor in such a composite, the resin is easily dispersedacross the entire sheet. Therefore, since it is possible to manufacturea high strength sheet, effective use in the sheet manufacturingapparatus is possible.

REFERENCE SIGNS LIST

-   -   1 resin    -   2 coloring material (coagulation inhibitor)    -   3 resin particles    -   4 mother particles    -   5 shell    -   10 crushing unit    -   11 crushing blade    -   15, 16 hopper    -   20 defibrating unit    -   21 introduction port    -   22 discharge port    -   30 classifying unit    -   31 introduction port    -   34 lower discharge port    -   35 upper discharge port    -   40 screening unit    -   46 introduction port    -   47 discharge port    -   60 distribution unit    -   66 introduction port    -   70 sheet forming unit    -   72 deposition unit    -   74 tension roller    -   76 heater roller    -   77 tension roller    -   78 winding roller    -   80 drying unit    -   81 first conveyance unit    -   82 second conveyance unit    -   83 third conveyance unit    -   84 fourth conveyance unit    -   85 fifth conveyance unit    -   86 sixth conveyance unit (pipe)    -   90 winding unit    -   92 cutting unit    -   94 packaging unit    -   100 mixing unit    -   150 composite supplying unit    -   151 supply port    -   200 bonding unit    -   1000 sheet manufacturing apparatus

1. A sheet manufacturing method comprising: a step of mixing fibers anda composite integrally including a resin and a coagulation inhibitor,the composite being a powder whose volume average particle diameter is 1μm or more to 100 μm or less, at least a portion of the coagulationinhibitor being arranged in a surface of the composite; and a step ofbonding the fibers and the composite.
 2. The sheet manufacturing methodaccording to claim 1, wherein the composite is a powder whose volumeaverage particle diameter is 5 μm or more to 35 μm or less.
 3. The sheetmanufacturing method according to claim 1, wherein a number averageparticle diameter of the coagulation inhibitor is 0.001 μm or more to 1μm or less.
 4. The sheet manufacturing method according to claim 1,wherein a coverage ratio of the surface of the composite by thecoagulation inhibitor is 20% or more to 100% or less.
 5. The sheetmanufacturing method according to claim 1, wherein the coagulationinhibitor is 0.1 parts by weight or more to 5 parts by weight or lesswith respect to 100 parts by weight of the composite.